American Mensa, Ltd.,
201 Main Street, #1101
Fort Worth, TX 76102
Via E-Mail Phone for inquiries about joining:
1 (800) 66 MENSA [1-800-666-3672]
Open to individuals who have scored in the top 2% on a standardized intelligence test. Founded in 1945 by R.Berrill and L.Ware. Name of Journal: Mensa Bulletin

Camelopard Society,
PO Box 16898,
San Diego CA 92116
Open to individuals who have scored in the top 2% on a standardized intelligence test. Founded in 1988 by Lendon Best. Name of Journal: G'raffiti

International Society for Philosophical Enquiry,
c/o Harry Callahan,
PO Box 34304,
Omaha, NE 68134
Open to individuals who score in the 99.9th percentile on a standardized adult intelligence test. Founded 1974 by Chris Harding. Name of Journal: Telicom

The International High Five Society,
3546 Devon Hill Road,
Toledo, OH 43606-1102
(419) 474-3809 FAX: (419) 474-1009,
e-mail: 72717.3507@compuserve.com.
High Five is open to anyone testing above the 95th percentile on a standardized test of intelligence.

Intertel,
PO Box 150580,
Lakewood, CO 80215
(303) 797-7210
Open to individuals who have an IQ at or above the 99th percentile on an accepted test. Founded in 1967 by Ralph Haines. Name of Journal: Integra

Mega Society,
c/o Rick Rosner,
5139 Balboa Blvd #303,
Encino, CA 91316-3430
Open to individuals with an IQ in the 99.9999th percentile. Founded in 1982 by Ronald K Hoeflin. Name of Journal: Noesis

One-In-A-Thousand,
PO Box 539,
New York, NY 10101
(Ronald K. Hoeflin, Founder)
Open to persons with measured IQs in the top 1/10% of the population. Name of Journal: Oath

Prometheus Society,
c/o Robert Dick,
13 Speer Street,
Somerville, NJ 08876
Open to individuals exceeding the 99.997th percentile of general intelligence. Founded in 1982 by Ronald K Hoeflin. Name of Journal: Gift of Fire

Sinistral SIG,
200 Emmett Ave.,
Derby, CT 06418
(203) 735-1759
Open to left-handed people whose IQs are in the top 2% of the population and who are eligible to be members of Mensa.

Triple Nine Society,
PO Box 29,
Dover, MA 02030-0029
Open to those individuals who score in the top 99.9th percentile on a standardized intelligence test.